纳米微晶纤维素-棕榈油的Pickering乳化液的制备及体外消化行为

以市售棕榈油(熔点为5℃)为乳化对象,利用棉短绒来源的1%纳米微晶纤维素(NCC)水分散液对其进行Pickering乳化(水相∶油相=7∶3,v∶v),分析不同酸解时间制备的NCC的乳化效果;同时,以游离脂肪酸的释放量为指标,研究NCC乳化液在模拟胃肠道中的消化行为。结果表明,酸解时间为3.0 h的NCC的Pickering乳化效果最好,不同酸解时间的NCC的Pickering乳液粒径均主要集中于1～10μm。NCC乳化液体外消化实验表明:1%的NCC形成的乳化液在肠液消化2 h时的游离脂肪酸释放量为830μmol/L,同样条件下,棕榈油对照组的游离脂肪酸释放量为480μmol/L。NCC含量越高,游离脂肪酸释放量越高,表明NCC乳化有助于脂肪的消化。纳米微晶纤维素的Pickering乳化特性在功能性脂肪酸及脂性活性物质的承载与传递中具有潜在的应用。

Preparation and in Vitro Digestion of Nanocrystalline Cellulose-Palm Oil Pickering Emulsion

Pickering emulsification of commercially available palm oil(melting point:5℃)was carried out using a 1%nanocrystalline cellulose(NCC)aqueous dispersion derived from cotton linters(aqueous phase∶oil phase=7∶3,v∶v),and the effect of NCC prepared by different acid hydrolysis time on emulsification performance was investigated.The in vitro digestion behavior in terms of free fatty acid release was estimated.The results showed that,NCC prepared with acid hydrolysis time of 3.0 h was optimal for Pickering emulsion,and the distribution of the particle size of NCC Pickering emulsions ranged from 1 to 10μm.The results of in vitro digestion test showed that,the higher the NCC content in emulsion,the higher levels of free fatty acids released,and 1%NCC emulsion in the simulated intestinal fluid(SIF)for 2 h showed a free fatty acid release of 830μmol/L,480μmol/L of the palmoil control group under the same conditions,suggesting the benefit of NCC for fat digestion.Pickering emulsion stabilized by NCC provided the potential to carry and deliver functional fatty acids and fat-soluble bioactives for human nutrition.